The two putative ribonucleotide reductase subunits of the Bacillus subtilis bacteriophage SPbeta are encoded by the bnrdE and bnrdF genes that are highly similar to corresponding host paralogs, located on the opposite replication arm. In contrast to their bacterial counterparts, bnrdE and bnrdF each are interrupted by a group I intron, efficiently removed in vivo by mRNA processing. The bnrdF i...

Homing endonucleases initiate mobility of their host group I introns by binding to and cleaving lengthy recognition sequences that are typically centered on the intron insertion site (IS) of intronless alleles. Because the intron interrupts the endonucleases' recognition sequence, intron-containing alleles are immune to cleavage by their own endonuclease. I-TevI and I-BmoI are related GIY-YIG e...

The DNA sequence has been determined of the 3' terminus from the mitochondrial large subunit ribosomal RNA (LSUrRNA) gene of the eukaryotic green alga Scenedesmus obliquus (strain KS3/2). The gene contains two intervening sequences with characteristic sequence motifs of group II and group I introns respectively. The exon/intron boundaries of the introns have been revealed by sequence determinat...

Group I intron endonuclease I-CreI is encoded by an open reading frame contained within a self-splicing intron in the Chlamydomonas reinhardtii chloroplast 23S rRNA gene. I-CreI initiates the lateral transfer or homing of this intron by specifically recognizing and cleaving a pseudopalindromic 19-24 bp homing site in chloroplast 23S rRNA genes that lack the intron. The gene encoding this enzyme...

Several group I introns have been previously found in strains of the Bacillus cereus group at three different insertion sites in the nrdE gene of the essential nrdIEF operon coding for ribonucleotide reductase. Here, we identify an uncharacterized group IA intron in the nrdF gene in 12 strains of the B. cereus group and show that the pre-mRNA is efficiently spliced. The Bacillus thuringiensis s...

Background: Recurrent pregnancy loss (RPL) is a common problem among couples, and acquired thrombophilia is the well-known etiology of RPL. The aim of this study was to establish the association between inherited thrombophilic gene polymorphisms and RPL. Methods: This case-control study was conducted on 50 women with unexplained RPL and 50 parous women with no history of miscarriage (age range...